Dysfunctional Voiding in Children

1. Dysfunctional Voiding in Children Hann-Chorng Kuo Department of Urology Buddhist Tzu Chi General Hospital

2. Development ofUrethral Sphincter • Specific striated sphincter muscle closely applied to the smooth muscle at membranous urethra and mid-urethra • A ring shape sphincter in early adolescence, which account for initial high voiding pressure in infancy and early vesicoureteral reflux • An omega shape shincter in adolescence after development of urogenital septum

3. Congenital Abnormalities • Myelodysplasia • Lipomeningocele • Sacral agenesis • Tethered cord • Cerebral palsy • Bladder extrophy • Posterior urethral valve • Anorectal malformations

4. Myelomeningocele • The most common form of NVD in children • Early detection and folic acid treatment markedly decrease spinal defects • Upper and lower motor bladder dysfunction and pelvic floor dysfunction may occur in thoracic or sacral lesions • Early prophylactic treatment of DESD by CIC, anticholinergics are beneficial

5. Myelomeningocele, detrusor areflexia and incontinence

6. Meningomyelocele & Bilateral VUR & Recurrent UTI

7. Lipomeningocele • Difficult to identify by physical examination, MRI is the best diagnostic method • Intradural lipoma results in disease and presentation • The most common urodynamic findings are consistent with an upper motor neuron lesion • DESD is less common • Detrusor hyperreflexia and areflexia can be found in this group of lesion

8. Sacral agenesis • Often discovered at older children with incontinence • Loss of the lower vetebral bodies by X-ray or MRI • Patients have stable neurological lesion • Patients may have no signs of denervation, hyperreflexia, areflexia, intact sphincter, sphincter dyssynergia

9. Tethered cord syndrome • Most commonly seen in patients after surgery for myelomeningocele • Isolated tethered cord is less common • Severe bladder dysfunction and refractory incontinence may occur • Surgical division of the filum may improve symptoms

10. Cerebral Palsy • Develops most commonly in premature infant • Infection and anoxia result in a non-progressive brain lesion and muscular disability • Continence is often delayed to develop but intact • Uninhibited detrusor contractions without DESD is the most commonly urodynamic finding • Pseudodyssynergia may occur

11. Cerebral palsy with frequency dysuria due to DI

12. Bladder extrophy • Characterized by extrophic bladder, abdominal wall defect, epispadias, pelvic diastasis, VU reflux, inguinal hernia • Staged reconstruction by abdominal wall closure, epispadias repair, bladder neck reconstruction and correction of VUR • Improved pelvic floor reconstruction after osteotomy has better continence rate • Bladder augmentation may be indicated

13. Posterior Urethral Valve • The most common cause of BOO in newborn • Present with incontinence and recurrent UTI • Severe PUV may be detected antenatally, mild form is found in older children • Bilateral hydroureter and hydronephrosis may develop in severe form of valve disease • Transurethral ablation of valve resumes normal bladder but bladder function depends • Anticholinergics, CIC and augmentation by ureter may be indicated

14. Anorectal Malformations • Rare congenital lesions of cloaca • Associated with congenital GU abnormalities in 20% with low and 60% high lesions,VUR, NVD, renal agenesis, renal dysplasia, cryptorchidism • Urethrorectal fistula may develop at at high, intermediate or low level • Neurogenic voiding dysfunction in 50% • Tethered cord is the main vertebral abnormality, which account for NVD

15. Dysfunctional Voiding • A group of neurologically intact children presents with incontinence, dysuria, large residual urine, recurrent UTI, unilateral or bilateral hydronephrosis • Urodynamically classified into small capacity hypertonic bladder, detrusor hyperreflexia, lazy bladder syndrome,non-neurogenic neurogenic bladder • Treatment bases on interaction of bladder and external sphincter

16. Patient evaluation – history • Antenatal GU abnormalities – hydronephrosis, enlarged bladder, open spinal cord defect • Past surgical history – detethering procedure, VP shunt, urinary diversion • Occurrence of UTI and antibiotics • Bowel habit, fecal incontinence, and stool softeners • Catheterization schedule, urine amount • Medication and adverse effects

17. Physical examination • Neurological examination – gait, discrimination of extremities, motor strength, DTR (S1,2), BCR (S2-4) • Sacral dimple, hair patch, lipoma • Enlarged bladder • Vincent curtsey • Anal tone, volitional contraction of pelvic floor muscles

18. Urodynamic study • Estimated bladder capacity: (age+2)x30 ml • Infusion rate: 10% of capacity • Catheter: <6Fr intraurethral dual channel catheter, suprapubic catheter is preferable for pressure flow study • Abdominal pressure by rectal catheter • Pelvic floor EMG – surface or needle • Measuring bladder compliance, detrusor pressure, and EMG activities coordination

19. Detrusor external sphincter dyssynergia (DESD) • Type 1: Onset of EMG activity with initiation of voiding • Type 2: intermittent inappropriate external sphincter contraction during voiding,which causes a reflex inhibition of detrusor contraction • Type 3: Persistent increased EMG activity during filling and voiding phases, which causes large residual urine and incontinence • Pseudodyssynergia: presence of urodynamic DESD in neurologically intact patient

20. Leak-point pressures • Detrusor leak-point pressure (DLPP): The detrusor pressure causing urinary leakage per urethrum in the absence of detrusor contractions • A DLPP of more than 40 cm water has a risk of upper tract deterioration • Valsalvar LPP (VLPP): Assessing urethral resistance by abdominal straining, a VLPP <60 cm water indicates intrinsic sphincter deficiency

21. Indications for urodynamic study in children • Spinal dysraphisms • Spinal cord injury • Cerebral palsy with voiding dysfunction • Sacral agenesis • Imperforated anus • Diurnal enuresis • Suspicious voiding dysfunction and UTI • Dysfunctional voiding

22. Urodynamic studies in children with dysfunctional voiding • Uroflowmetry with surface EMG • Cystometry with abdominal pressure and EMG • Pressure flow study recording Pves,Pabd, Pdet, EMG activity, and uroflowmetry • Videourodynamic study by suprapubic catheter or intra-urethral catheter

23. Uroflowmetry – flat flow pattern with non-relaxing ES

24. Uroflowmetry – Staccato pattern and poor relaxing ES

25. Videourodynamics via cystostomy pressure flow study

26. Dysfunctional Voiding Associated with the followings • Diurnal enuresis • Urinary urgency • Urinary frequency • Constipation • Urinary tract infection • Vesicoureteral reflux

27. Pathogenesis of dysfunctional voiding • Increased voiding pressure during voiding with contraction of the urethral sphincter • Dysfunctional bowel evacuation and constipation • Treatment directed at urodynamic abnormalities reduce the incidence of breakthrough UTI and increase resolution of vesicoureteral reflux

28. Typical spinning top voiding cystourethrography

29. Development of dysfunctional voiding • Long-standing pelvic floor dysfunction results in paradoxical sphincter contraction • Pelvic laxity • Inappropriate stimulation of guarding reflex results in inhibition of detrusor contraction

30. Detrusor instability without dyssynergic external sphincter

31. Dysfunctional voiding and Urinary tract infection • Elevated postvoid residual urine • Host resistance – ability of bladder to wash out pathogens • Well hydration, void with strong stream, and complete voiding are important in prevention of UTI • Treatment aims at relaxation of the pelvic floor rather than the bladder

32. Recurrent UTI in siblings with Dysfunctional voiding

33. Non-neurogenic neurogenic bladder– Hinman syndrome • The severest form of dysfunctional voiding • Symptom complex including nocturnal enuresis, diurnal enuresis, constipation, encopresis, UTI, and upper tract dilatation • Uninhibited detrusor contractions and dyssynergic external sphincter

34. Treatment of non-neurogenic neurogenic bladder • Voiding retraining • Biofeedback • Anticholinergic therapy • Hypnosis • Psychotherapy • Management of constipation • Antibiotics • Clean intermittent catheterization

35. Dysfunctional voiding and Vesicoureteral reflux • Play a major role in etiology of congenital VUR • Important in development of VUR in older child without congenital VUR • Responsible for reflux exacerbation and renal scarring • Therapy to VUR should aim at correction of dysfunctional voiding

36. Bilateral VUR in a girl with Dysfunctional voiding

37. Right VUR and DI without dysfunctional voiding

38. Resolution of VUR after Anticholinergic therapy

39. Urodynamic studies in infants • High voiding pressures (160cm water) with low bladder capacity in infant with gross dilating reflux • Voiding pressure in infant without reflux is 80 cm water • By age 2 years, voiding pressure diminished (70 cm water) and capacity increased, but unstable detrusor remain

40. High voiding pressures in infancy • Transient functional bladder outlet obstruction • Boys with high grade reflux have dilated posterior urethra • Higher voiding pressure is seen in children with grades IV and V reflux • Normalization of voiding pressures explains high rate of reflux resolution in childhood

41. Urodynamic studies in older children • Up to 60% of children with reflux have urodynamic abnormality • Detrusor overactivity and sphincter dyscoordination • Primary sphincter overactivity is more associated with high grade reflux and renal scarring • Bladder instability improves over time

42. Pitfalls in urodynamic study in infants and children • Poor cooperation of patient • Appropriate size of intra-urethral catheter – 3 Fr, 5 Fr, 7 Fr? • Frequent increased abdominal pressure • Different infusion rate and compliance in different age • Differential diagnosis of volitional voiding and detrusor overactivity

43. Urodynamics and Clinical course of VUR • Treatment of detrusor overactivity with anticholinergics improves resolution or improvement in VUR than stable bladders • A higher surgery rate in stable bladder with VUR • Controversy remains in correlation of urodynamic abnormalities with grades of VUR and anticholinergic treatment with resolution rate of VUR

44. Resolution of VUR and improved DI after anticholinergic and CIC in myelomeningocele

45. Dysfunctional elimination syndromes (DES) • Children are both infrequent voiders and constipated • Associated with an increased risk of urinary tract infection • With or without reflux • Incontinent day and night with fecal soiling • Observed to engage in holding maneuver to avoid urination and defecation

46. DES – A learned habit • A learned habit acquired during toilet training • Most often occur in girls • Recurrent cystitis due to short urethra and bladder colonization • Congenital VUR or secondary VUR due to these aberrant toilet training habits

47. Breakthrough UTI and Dysfunctional voiding • Girls with history of voiding dysfunction have higher rates of breakthrough UTI (4 times more common in DES) • Unsuccessful surgical outcome was seen in children with DES • Adequate hydration, timed voiding, stool softeners, laxatives, as well as anticholinergics may be helpful

48. Voiding dysfunction without UTI • Children with mono-symptomatic enuresis have a very low urodynamic abnormality • VUR has been found in child with frequency urgency and urinary incontinence without history of UTI • 15% of children had positive urodynamic findings and 16% had renal scarring

49. Diurnal incontinence due to pelvic floor hypertonicity & DI

50. Urge incontinence in a girl with dysfunctional voiding & DI